Anti-back-siphoning flushing apparatus



Patented Mar. 25, 1941 UNITE stares PATENT QFFICE ANTI -BACK- SIPHONIN G FLUS HING APPARATUS 5 Claims.

This invention relates to anti-back-siphon flushing apparatus, and more particularly to a flushing device for flushing a closet bowl wherein back siphoning of water from the toilet bowl into the water supply line, or into the water storage tank of the flushing device is prevented, or wherein back-siphoning of the water contents of the storage supply tank into the water supply line is prevented.

The problem of providing a mechanism for the flushing of the closet bowlso as to absolutely prevent all possibility of back-siphoning of water from the closet bowl or flushing supply tank and still to provide an efiective and easily actuated flushing mechanism is of long standing in this art.

Many attempts have been made to provide a device for flushing a closet bowl through which back-siphoning so as to contaminate the water supply line would be impossible. In large installations wherein there are many valved outlets connected with the water supply line, backsiphoning has occurred through conditions which it is difficult to understand how the sudden reduction in pressure caused by the opening or many outlets could develop a sufiicient back pressure as to enable back-siphoning to occur. Such back-siphoning, however, has been observed where the reduction in pressure has been suflicient and has resulted in a direct application of suction over the contents of the toilet bowl wherein a more or less whirl-wind condition has been set up in the air above the water in the toilet bowl with the result that the contents of the bowl have been drawn back into the water supply line even though this has required the drawing of the water through a considerable air gap between the level of the water in the bowl and the point of the passage in the bowl into which the water had to be drawn.

In order to avoid contamination of the water supply line by the backdraft of water from a water-closet installation, it is essential that all water which is in fluid contact with the water in the bowl be prevented from being drawn back into the water supply line, thus water in a supply tank or flushing tank must be prevented from being drawn back into the water supplyline because this water in such a supply tank may also become contaminated with bacteria from the water within the bowl.

It is therefore an object of this invention to provide a flushing device for water-closets through which ba'ck-siphoningof either the water (Cl. i -26) from the closet bowl or from the supply tank for flushing the closet bowl is prevented.

Another object of this invention is to provide a flushing device of the pressure tank type which is so constructed as to avoid all possibility of back-siphoning and which is likewise so constructed as to enable the quick, easy and effective delivery of the water from the pressure supply tank to the closet bowl to carry out the flushing operation.

Another object of this invention is to provide a flushing device for closet bowls including a pressure tank containing water under pressure wherein a discharge valve is provided which is of instantaneous opening upon actuation of the actuating member for said valve, and which will remain open Without maintaining the actuating member in depressed position permitting free flow of water from the pressure tank to the closet bowl to effectively flush the same after which the said valve member will close.

Another object of this invention is to provide a flushing device for closet bowls which includes a pressure tank containing water under the line pressure and which pressure tank is provided with a discharge valve and relief valve means which may be withdrawn from the tank through a single opening therein in order to elfect repair or replacement of the parts thereof should such be required without the necessity of removing the tank.

Another object of this invention is to provide a flushing device for closet bowls which includes a pressure tank for the maintenance of a flushing supply of water under pressure and a discharge valve including means for initially releasing the pressure within the tank on flushing and with said release of initial pressure, to maintain the discharge valve away from its seat until the flushing operation has been completed by the withdrawal of the required volume of water from the pressure tank. 7

Other objects and advantages of this invention it is believed will be apparent from the following detailed description of a preferred embodiment thereof as illustrated in the accompanyin'g drawing.

In the drawing:

Figure 1 is a front elevation of a flushing apparatus embodying my invention illustrating the same partly in vertical section.

Figure 2 is a sectional plan view taken substantially on the line 2-2 of Figure 1.

Figure 3 is a similar sectional plan view taken substantially onithe. line 3-3 of Figure 1.

Figure 4 is an enlarged fragmental mid-sectional elevation illustrating the relief and breather means embodied in my invention.

Figure 5 is a fragmental enlarged mid-sectional elevation illustrating the discharge valve embodied in my invention and illustrating the same in closed position.

Figure 6 is a similar mid-sectional elevation from the view of Figure 5 and illustrating the discharge valve in fully opened position.

In the preferred embodiment of my invention as illustrated in the accompanying drawing, I indicates a tank which may be of any suitable or desirable construction and which as herein illustrated includes a central cylindrical section formed of sheet steel having welded thereto a bottom 2 and a top 3 so as to provide a fluidtight pressure flushing tank.

In the preferred illustration as given, the tank I is provided with a single discharge and supply opening in the bottom 2 and. with an air breather opening 4 in the top 3, which air breather opening 4 is connected through the medium of a conduit 5 with the discharge duct or conduit 6 below the opening in the base 2.

In the preferred form of my invention as illustrated, the relief valve assembly includes a casting I having an annular flange 8 at its upper end upon which a gasket 9 is mounted so that the casting 1 as it is secured to the bottom 2 by means of a plurality of bolts l0 forms a fluidtight connection therewith with the gasket 9 extending inwardly over the surface of the flange 8 to provide the seat II for the discharge valve I2.

The casting I is formed with a breather branch I3 into which the breather conduit 5 extends at a point below the seat so that the discharge conduit 6 below the seat II for the valve I2 is at all times open to the atmosphere at a point above the level of the water within the tank Likewise formed in the casting I may be a branch I4 having a fluid passage I5 therethrough to which the conduit l6 connected with the water main or supply water under pressure is connected and to which the intake pipe H which extends up into the tank I is likewise connected. The intake pipe extends in the tank I to a point near the top 3 and to a point above the water level indicated at l8.

Should a back pressure develop within the water main and be exerted through the conduit I6, passage l5 and up through the intake pipe this reduced pressure first exerts itself in the space within the tank I above the water level.

Connected with the breather line 5 within the tank I is a breather branch IS in which a valve 20 is mounted. As herein illustrated, the valve 20 is formed by positioning within the branch I9 a seat member 2| having a passage 22 of reduced diameter extending therethrough.

A ball 23 is mounted in the branch I9 and is held from displacement by means of a stop pin 24. When the ball 23 is moved to the open position as indicated in Figure 4, it drops away from the seat 2| and reduced passage 22 under the influence of gravity leaving afree passage through the seat 2|. Thus as soon as a reduced pressure occurs within the tank I due to the development of a back pressure within the water main, the ball 23 falls away from the seat 2|, relieving the pressure within the tank I and overcoming any tendency of the water to be withdrawn from the tank I into the water supply main. This inlet valve into the breather pipe is located Well below the level of the upper end of pipe Hence if a reduction of pressure occurs in supply I1, the opening of the ball valve will immediately cause the water level to drop further from the upper end of the pipe IT. This also operates to keep the water level I8 well down below the level of the mouth of the pipe II. On this account, any reduction of pressure in the supply pipe could only withdraw air from the space above the water lever l8, and could not draw any water from the tank back into the supply line.

The closure casting 'l likewise provides a means for carrying the valve I2 and its actuating mechanism. As herein illustrated, this discharge valve I2 includes a cup 25, a cap 26, and a relief valve 21. The cap 26 is fixed in position with relation to the casting l by means of bolts 28 and a plate 29 which engages the upper edge of the cap 26 and as the nuts 30 are tightened, forces the cap 26 against the upper ends of the guide sleeves 3| mounted on the bolts 28, clamping the cap 26 in position. The cup 25 is free to float within the downwardly extending annular flange 32 of the cap 26 and is guided in its movement toward the seat II by the sleeve 3| carried by the bolts 28 so that the cup 25 accurately engages the seat II on closing.

The cup is formed at its central point with an upwardly extending tubular relief valve guide and seat 34 upon which the head 35 of the relief valve tube 33 seats. As indicated in Figure 7, the head 35 may be formed as a separate part from the tube 33 and be secured thereto by means of a screw 36. The relief valve tube 33 is formed with a plurality of radially extending passages 31 below the head 35, which passages communicate with the passage formed axially of the tube 33. A stop shoulder 38 is formed on the tube 33 to prevent the same being displaced upwardly out of the bleeder passage 39 formed through the seat 34 in the cup 25.

The upstanding annular wall 40 of the cup 25 overlaps the downwardly extending annular wall 32 of the cap 26 and is spaced therefrom slightly so as to permit relative freedom of movement of the parts and also so as to permit the inflow of water from the tank I into the cup 25 to maintain the cup 25 upon the seat II.

Mounted within the discharge conduit 6 and casting l is a valve actuating mechanism herein illustrated as including an actuating rod 4| which extends through the packing gland 42 into the interior of the discharge conduit 6. Secured to the rod 4| at its inner end is a cam 43. Secured to the rod 4| at its outer end is an operating handle 44.

In order to retain the actuating rod 4| in a position to normally maintain the valve |2 closed, a spring 45 is provided which is mounted upon the rod 4| having its one end held by a pin 46 carried by the rod 4| and its opposed end secured as indicated at 41 to a stationary portion of the assembly as, for example, to the gland nut. The spring 45 is a torsion spring acting to normally rotate the rod 4| to a position where the cam 43 permits the valve I2 to close.

The operation of the anti-back pressure flushing apparatus embodying my invention is:

The interior of the tank I being at all times open to inflow of water from the water main, fills with water when the valve I2 is closed, trapping air in the upper portion of the tank I and compressing the air to the extent possible under the pressure of the water in the supply main. Thus when the pressurewithin the tank I becomes equal to the pressure of the water in the line, further inflow of water ceases. The parts are so related as hereinabove set forth that the inflow of water ceases while the water level I3 is preferably still below the outlet of the intakepipe IT.

The condition illustrated in the drawing is an extreme condition and under normal conditions of water pressure, the Water level in the tank would be considerably below that indicated at I8. 7

As the water flows into the tank I and reaches the level of the breather branch I9, water tends to rush through the opening 22 formed in the seat 2|, which rush of water carries with it the ball 23, closing this passage against further outflow of water. Thus it has been found that only a very small quantity of water will pass through the breather line on filling the tank I. As the conduit 5 extends into the casting "I below the valve I2, this water is delivered into the closetbowl.

As there is a considerable branch of the conduit 5 above the breather branch I9, the rush of water into the breather branch I9 does not result in water backing out of the tank I at the top thereof.

With the tank thus filled with water under pressure, the flushing of the closet-bowl is accomplished by merely hitting the handle 44 and without maintaining the handle 44 in an open po-- sition. This is accomplished due to the following action:

The cam 43 immediately raises the bleeder valve tube 33 up to raise the head 35 off from the seat 34. The small quantity of water within the cup 25 immediately passes out through the passages 31 and tube 33 permitting the cup 25 to move from its seat and be retained oif from its seat due to its buoyancy and due to the rush of water under the cup 25 out through the discharge conduit 6. As the handle 44 has been released, the cam 43 has fallen to the position indicated in Figure 5, in which position all parts are permitted to again fall to a position to close the valve I2. As long as water is rushing out from the tank I, this does not occur. Due to the fact that the water inlet into the tank I is of much smaller size than the water outlet, the tank I soon empties, permitting the cup 25 to return to its seat II, and as the cam 43 has already been rotated out of the position to raise the bleeder tube 33 by release of the handle 44 and action of the torsion spring 45, the valve I2 is closed, permitting the tank I to again be filled and water to pass between the annular rims and to again fill the cup 25.

It is essential in the operation of this construction in order to secure a discharge valve which may be operated by merely pushing downward on the handle 44 and without the necessity of holding the handle 44 down, to maintain the volumetric contents in the cup 25 small so that there does not have to :be bled, through the ports 31 and through the tube 33, a large volume of water. This of course is relative with relation to the size of the outlets and the pressure in the tank I, but I have found in practical operation that this operation is most readily insured by concaving the cap 26 inwardly into the cup 25 materially so as to reduce the capacity and hence the volume of water trapped between. the cap 26 and cup 25.

It will be obvious from the foregoing that when the bleeder tube 33 is raised upwardly by operation of the cam 43, that the shoulder 23 of said tube engages the under portion of the cup25, raising the cup 25 01f of the seat, thus initially permitting the water to rush under the cup 25. The reduced volume of water between the cup 25 and. the inwardly concave cap 26 is thus related to the force exerted b-y this outrush of water in connection with the bleeding of the cup 25 through the ports 31 and tube 33 that the valve I2 remains open until the water has been drained from the tank I.

As illustrated in Figs. 1 and 4, the substantially vertical extension 5 that is vented to the atmosphere, is in substantially axial alignment with the bottom. opening at which the fitting 'I is mounted. This feature is advantageous in assembling the parts as the connection or opening to the upper head 3 of the tank, guides and centers the fitting 'I as it is being pushed up into place, and also facilitates the rotation of the fitting I on its own central axis to bring the circum=ferentially disposed bolt openings in the fitting into alignment with the circumierentially disposed bolts IIl. These circumferentially disposed bolts are indicated in Fig. 2.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but by invention is of the full scope of the appended claims.

I claim:

1. In an anti-back-siphoning flush valve, the combination of a pressure tank, means for admitting water under pressure to within the pressure tank having its delivery point for the water located above the level of the water within the pressure tank when filled, means for controlling the discharge of water under pressure from the pressure tank, said means including a flush valve composed of a :cup and a concave cap telescopically mounted with relation to said cup to reduce the volumetric contents between the cup and the cap, and a bleeder valve mounted in the cup to bleed the contents therefrom, means for actuating the bleeder valve and to raise the cup into the concave can so that the discharge opening from the pressure tank is open substantially simultaneously with the opening of the bleeder valve whereby the cup remains open on release of said actuating means to complete the discharge of the water from within the pressure tank through the discharge opening, and a breather conduit mounted in the pressure tank with its inlet located below the level of said delivery point, and extending down therefrom and into the discharge duct below the flush valve, and having a relief valve opening into the pressure tank at a point near the water level therein.

2. In an anti-back-siphon flushing device, the combination of a pressure tank, means for admitting water under pressure to within the pressure tank at a point above the level of water within the pressure tank when filled, a flush valve mounted within the pressure tank to control the discharge of water therefrom, a breather conduit mounted within the pressure tank extending therefrom at the top of the pressure tank and extending into the discharge from the pressure tank at a point below the flush valve, the breather conduit having a relief valve opening into the pressure tank within the pressure tank near the water level therein, below the level of the said point of admission of the water, and the breather conduit and flush valve being mounted in unit assembly to permit withdrawal thereof through the pressure tank discharge opening.

3. In an anti-back-siphon flushing device, the combination of a pressure tank, means for admitting water under pressure to the pressure tank at a point above the level of the water within the pressure tank when filled, a flush valve mounted within the pressure tank to control the discharge of water under pressure therefrom, said flush valve including a cup seated upon a valve seat at the discharge opening of the tank; the cup being adapted to receive water from within the pressure tank, a concave cap telescopically mounted with relation to said cup, said cup being mounted to move away from said seat to telescope within said concave cap, a tubular guide and valve seat located at the bottom of the cup, a tubular bleeder valve mounted therein and movable up into the cap, having passages through its wall operating when the valve is raised to admit water to flow down the tubular bleeder valve to the discharge opening, and means for actuating the bleeder valve and cup to respectively open the same whereby the bleeder valve and cup are opened simultaneously and remain open upon release of said actuating means until the contents of the pressure tank have been discharged therefrom.

4. In a structure of the class described, a tank having inlet means, and a discharge opening at its lower end, a waste pipe having a substantially vertical extension adjacent its upper end connected to the tank cover for venting the waste pipe to the atmosphere, a flow-controlled valve means mounted in said tank over said discharge opening, a bleeder valve mounted in the firstnamed valve with means foractuating the same, first to open the bleeder valve and then open the other valve, said waste pipe extending downwardly and connecting at its lower end to the discharge opening, said tank having a bottom opening aligning with the said vertical extension, and a base fitting carrying said waste pipe and carrying said flow-controlled valve means removably seating on the tank bottom at said bottom opening, and insertable into said opening from below, said base fitting having circumferentially disposed bolts around the bottom opening.

5. In an antiback-siphon flushing apparatus for closet bowls, the combination of a water pressure tank, a water supply pipe having its delivery opening slightly below the cover wall of the tank, a waste tube communicating with the outlet from said tank below the discharge valve and communicating with the atmosphere above said tank, and a check valve mounted in said tube within the tank to open inwardly, said check valve being situated near the liquid level in said tank when filled and below the level of said delivery opening.

FRANK B. CHARROIN. 

